NC-2009 SSc8: Light Pollution Reduction

  • NC CS- SSc8 Light Pollution Reduction- Credit Requirements
  • Interior and exterior lighting

    Addressing both interior and exterior lighting, this credit seeks to reduce light pollution that can block our view of the night sky and cause human health problems as well as ecological problems for many birds, insects, and other animals. Light pollution often represents nighttime lighting that isn’t needed, wasting energy while causing light trespass and contrast, reducing visibility.

    SSc8 YouTube video

    Better lighting = Better safety, less energy

    Many people think that more lighting means better nighttime safety and security. However, too much exterior lighting can make outdoor and parking areas less safe by creating high contrast between lit and unlit spaces. Among other problems, when the human eye is flooded by bright light, it becomes harder to adjust to darker areas and shadows. Too much exterior lighting also means unnecessary energy consumption. Some objectives to keep in mind when striving for safe, efficient, and aesthetically pleasing lighting design are lighting uniformity, low contrast, no glare, and preventing light from spilling off the site. This can be achieved through judicious selection of fixtures with full cutoffA full cutoff luminaire has zero candela intensity at an angle of 90 degrees above the vertical axis (nadir or straight down) and at all angles greater than 90 degrees from straight down. Additionally, the candela per 1,000 lamp lumens does not numerically exceed 100 (10%) at an angle of 80 degrees above nadir. This applies to all lateral angles around the luminaire. that direct light toward the ground but prevent it from shining up into the night sky.

    Full-cutoff luminaires reduce light pollution, improving views of the night sky.

    The four requirements can make it complicated

    This credit has four separate requirements, which can make compliance complicated—though not necessarily difficult. One addresses indoor lighting spilling to the outdoors, and three deal with exterior lighting, including façade lighting, site lighting of areas like pathways and parking lots. In most circumstances, these requirements are relatively easy and cost-neutral to meet. The biggest challenge often comes in dealing with light-trespass limits—light bleeding off the project site into a neighboring site—on projects with small or constrained sites. You will also need to attain low lighting power densities per ASHRAE 90.1-2007, which is a good general practice and won’t require you to compromise on aesthetics or cost.

    LEED boundary is important

    You’ll need to pay careful attention to establishing a LEED project boundary, which plays an important part in meeting light trespass requirements. Involve an exterior lighting designer (or landscape architect) early in the design process to develop photometric plans and guide fixture selection during design.

    FAQs for SSc8

    Are residential spaces exempt from the interior lighting calculations?

    Yes, as of 4/1/12 per LEED for Homes 2008 Interpretation #10147, “residential spaces (dwelling units only) within the scope of other LEED projects are also exempt from the interior lighting requirements.”

    Do existing fixtures need to be included in the exterior lighting calculations?

    Yes, if they are within the LEED project boundary.

    Can the Application Guide for Multiple Buildings and On-Campus Building Projects be used for the exterior lighting requirements?

    Yes, as long as the entire site meets the requirements.

    Can a mix of Option 1 (opaque surfaces) and Option 2 (automatic controls) be used to meet the interior lighting requirements?

    Yes.

    Are hospitals exempt from interior lighting requirements?

    No, hospitals are not exempt from the interior lighting requirements.

    What effect did the November 2011 ASHRAE table 9.4.6 Addendum i have on exterior lighting power allowances?

    Significant reductions for tradable surfaces in LZ1 and LZ2 and some in LZ3. See the new table for details. It also added lighting power allowances according to light zones, removed a 5% adder, and introduced a base site allowance. Suggest revising response and adding a link to the Addendum i available for free download on ASHRAE website.

    What about zero lot line projects, where is the boundary?

    You can use the curb line.

    To calculate building façade lighting power density, how do you determine the area used in the calculation?

    Use only the area that has measurable light on the surface; baseline and proposed are the same.

    Where are vertical footcandles measured at the site boundary?

    At grade level.

    Is signage included in the LPD calculations for building façades?

    No, per ASHRAE table 9.4.5, you can exclude lights in display windows, advertising, and directional signs as long as they are switched separately from other lighting.

    Does uplight that is under a canopy count towards the limitation of total initial design fixture lumens at 90 degrees or higher from nadir?

    If the canopy blocks 100% of the light then yes, but this is unlikely. Any light spillage needs to be counted toward the uplighting limit, but calculating this can be difficult. Using downlights is recommended instead.

    Is flag lighting exempt from this credit?

    Not currently, but USGBC is looking at exempting flag lighting from LEED v4 requirements.

    Are city-owned lights within a project's property required to comply with credit requirements?

    According to LEED InterpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. #10236, street lighting that is required by the governmental authorities to be installed within the LEED project’s lighting boundary (whether existing or new) does not need to be included in any of the calculations.

    For campus projects, do all existing light fixtures need to comply with credit requirements at the time of a project's submittal?

    All existing fixtures within the LEED project boundary would need to comply with the SSc8 requirements at the time the project is submitted for review. However, if the project elected to use the campus property boundary as the "lighting boundary" for SSc8 as allowed by LEED Interpretation #10236, existing fixtures within the lighting boundary, but outside the specific LEED project boundary would not have to comply with any of the SSc8 requirements. Essentially, the "lighting boundary" is only used in such circumstances for evaluating that the light trespass requirements are met at that boundary by lighting located within the LEED project boundary.

    What advertising lights or signs must comply with credit requirements and which are exempt?

    Advertising and directional signage, as explained in Addendum i of ASHRAE 90.1-2007, and further defined in the Users Manual for ASHRAE 90.1-2007, is exempt.  Essentially, that means that internally illuminated advertising signs are exempt, but those illuminated by lighting that is not ‘integral’ to the signage itself must be included in the calculations.

Legend

  • Best Practices
  • Gotcha
  • Action Steps
  • Cost Tip

Pre-Design

Expand All

  • Designate one responsible party to oversee exterior lighting-related LEED credit requirements. For large projects, this person may be the civil engineer or landscape architect. For small projects it may be the architect, lighting designer, or other relevant team member.


  • Identify the building owner’s goals for occupant safety and comfort as well as for architectural lighting, including façade lighting. Include these goals in the Owners Project Requirements for EAp1: Fundamental Commissioning


  • One of the biggest barriers to reducing light pollution is the cultural and aesthetic affinity for brightly lit buildings. Owners can play an important leadership role in contending with these expectations, establishing aesthetic goals that do not include excess lighting for purely aesthetic purposes. The design team can play an important role by maintaining low levels of lighting and highlighting specific façade architectural features with focused, low intensity lights.


  • Projects that demand brightly lit facades and entrances, such as casinos, hotels, theatres and commercial complexes, may have a hard time reconciling these desires with the requirements of this credit. Deliberate lighting design can forge a compromise between the desire to emphasize the building facades and the need to eliminate light pollution in order to meet the credit requirements.


  • Identify the urban lighting zone as defined by IESNA RP-33, based on the population density of the neighborhood, in order to establish lighting requirements.


  • Finalize the LEED project boundary in coordination with other LEED credits. The responsible party and the project team should identify the lighting fixtures close to the boundary that will be part of the lighting trespass analysis.


  • Projects with a zero lot line may choose to use the curb as the LEED boundary for the purposes of documenting light trespass only, while using the site boundary for other credits. This is one of the few exceptions to the rule that the LEED boundary and corresponding site area be consistent across multiple credits. Sites that abut public rights of way may similarly use the curb to establish the site boundary for the purposes of LEED documentation. It can be challenging for projects with zero lot lines or with little open space to meet the maximum exterior illuminance requirement of 0.1 footcandles at the site boundary. Project teams are only responsible for lights that are part of their project. For example, municipal lights about which the project has no control do not need to be considered. 


  • Campus projects can choose whether to comply with the requirements for the building site boundary or to meet the light trespass requirements for the campus as a whole. For a project on a campus, choosing to meet the light trespass requirements at the building level can be very difficult.


  • Identify local or regional lighting laws or required lighting levels for rights-of-way that may apply to the project site. These regulations may help teams identify areas to focus on when dealing with lighting trespass in the design.


  • Discuss fixture and lamp options with the landscape designer, civil engineer and other project team members, focusing on both reducing overall lighting power density, and on avoiding light trespass. Avoiding light fixtures that shine up into the sky is the easiest way to reduce light pollution and make better use of lighting. This can be done by eliminating exterior lighting entirely or by selecting “cut-off fixtures” with opaque covers that direct light downward.


  • Local or regional laws that regulate lighting levels typically do not require minimum input power in watts. Going beyond these local requirements by selecting energy-efficient fixtures can help your project meet codes for comfort and safety goals without compromising energy efficiency.


  • The credit requires a photometric study on site lighting that may add minor consultant costs but will add value by optimizing the design.


  • Optimizing lighting can eliminate unnecessary costs for extra lights and high-power fixtures.


  • Many smaller fixtures may make for a better layout than fewer high-wattage ones. The designer should be able to advise about additional infrastructure costs associated with an atypical lighting design. Low power density and light intensity may require higher first costs for fixtures that will save electricity costs during operations.


  • Rebates and incentives on the federal, state, and local levels are available for low-power and Energy Star lamps.


  • Safety concerns are not typically a valid excuse for higher exterior lighting allowances. Despite a perception of better safety with brighter lighting, floodlights can often create areas of deep shadow, and the high contrast can be difficult for the human eye to navigate. Use good design, downlights, and work with the owner to address any concerns.

Schematic Design

Expand All

  • Interior lighting


  • Be aware of all requirements for interior lights so that fixtures do not direct light through windows to the outdoors. Identify locations where fixtures might have a direct line of sight to a window or other opening. The lighting designer should either eliminate those fixtures from the design, provide shades to prevent more than 10% of light from shining outdoors, or include controls to reduce the input power by 50% between 11 p.m. and 5 a.m.


  • Interior lighting cannot spill out of the windows after business hours, defined as 11 p.m. – 5 a.m. in the credit requirements. Window coverings or automatic controls like timers, occupancy sensors, or master switches have to shut off or reduce the input power by 50% for all non-emergency indoor lights during that time.


  • Fixtures that throw 50% or more of the cone of light out a window are likely to present problems.


  • To avoid letting this credit slip through the cracks, project owners or architects should ask the lighting designers at the outset of the project how they plan to achieve each aspect of the credit.


  • Additional light controls and automatic window screens may add to construction costs, but controls can reduce electricity consumption.


  • Exterior lighting


  • Identify the project location and IESNA-designated zone to determine the threshold for exterior lighting levels.  Utilize resources like the website www.citydata.com to identify relevant population density and appropriate designation.


  • The lighting designer includes the design intent in Basis of Design for EAp1: Fundamental Commissioning, for all outside lighting requirements, listing minimum illuminance in footcandles, lumens, or candela for all spaces with controls, fixture requirements and design approach.


  • The lighting designer then develops the exterior lighting layout and selects fixtures that optimize light with low power use.


  • Nadir illustratedTo determine the total power density for the project, the lighting designer tabulates all exterior space and identifies the wattage of selected fixtures to compare it with the LPD allowable by ASHRAE 90.1-2004, Exterior Lighting Section. The selected fixtures should have full shielding or cutoff to reduce light directed toward the night sky.


  • The lighting designer develops a photometric study for exterior lighting intensity, the impact of shades and cutoff fixtures, and light trespass from the project boundary. Use the photometric study to inform any changes in the design.


  • The key to achieving this credit is to find the optimum balance between lighting quality and lighting energy consumption. It is often assumed that more light is better, but a low level of uniform lighting throughout a site will eliminate the need to install bright halogen lamps that illuminate some areas and leave others dark in contrast.


  • Exterior lighting includes all ground lighting, all façade lighting, flag lighting, any rooftop or terrace lighting, and any other fixtures outside the building. Pay careful attention to exterior light fixtures and light levels at building entrances close to the LEED site boundary.


  • Revisit the LPD calculations to make sure any design changes maintain the threshold limits.


  • ASHRAE’s exterior lighting density table lists exterior spaces under two categories. Tradable surfaces are those where the average LPD of all those surfaces are within the total LPD limits. For example, in LZ4, both sales canopy lighting and stairway lighting have a maximum of 1.0 Watts/ft2. The project may decide to increase sales canopy lighting to 1.1 Watts/ft2 as long as the stairways compensate with a decreased LPD of 0.9 Watts/ft2 (given that the surfaces are the same area) so that the average of the two is 1.0 Watts/ft2. For non-tradable surfaces, such as bank ATMs, each space must individually comply with the ASHRAE requirements. Identify whether exterior surfaces are tradable in order to provide flexibility.


  • A photometric study will facilitate communication about lighting levels among the designer, owner and the design team. The study entails computer modeling simulating the lighting intensity of the designed layout in footcandles, lux or candela. It allows the designer to see the resulting output, with iterative design options as the fixtures are reduced or replaced. Typically the photometric study measures light levels in a 10’x10’ grid. The analysis also investigates the maximum initial illuminance value at horizontal and vertical limits on the site boundary to ensure they are within the limits of the project zone. If you find that lights are above the threshold, the designer may want to explore alternative numbers of fixtures and fixture types and present these alternatives to the owner, who makes the final decision.


  • Avoid aiming light at highly reflective site and ground surfaces, such as white pavement and water features, which can exacerbate light pollution. The photometric study may not capture these characteristics.


  • Some lighting manufacturers will offer to perform a photometric study of your site if your team selects their product for the project.


  • Security-oriented lighting designs such as those for prisons, parking lots, and walkways often focus too much on big, bright lamps. This can be counterproductive, creating high contrast between lit and unlit spaces, worsening visibility in both places. Use more moderate, uniform light levels for improved designs.


  • Some types of lighting are exempt from the ASHRAE limits on power density. Examples include advertisement signage, transportation signage, athletic fields, storage, and historic landmarks and other public monuments. Refer to Exceptions under ASHRAE 90.1 2004 Section 9.4.5.


  • The lighting intensity of conventional fixtures such as halogens, incandescents, and sodium halide lighting, drops off significantly after the first year of operation. LED or fluorescent fixtures will better maintain their lighting intensity at the level of the installation—contrary to the common perception that low power wattage fixtures, such as LEDs or fluorescents, have low lighting intensities.


  • Full cutoff fixtures can generally be specified at zero cost premium.


  • Cost premiums for this credit may come from the higher number of (shorter) poles and fixtures needed to achieve greater lighting uniformity.


  • New fixtures like LEDs with high lighting levels but low power density may cost more than conventional halogen fixtures, but most of the new fixtures have longer life and are less expensive to operate due to low electricity use and infrequent lamp replacement.


  • Costs for the photometric study can be decreased if manufactures agree to do their own calculations, which is common if you select their fixtures.

Design Development

Expand All

  • Come to an agreement among the owner, landscape designer and lighting designer about the appropriate lighting levels and site lighting distribution.


  • Demonstrate to the owner the project team’s decision about lighting levels for the final design. Owners may need to be shown similarly lit areas to understand the implications of a shift from a brightly lit façade and terrace.


  • Locally mandated lighting levels for exterior fixtures higher than LEED-mandated ASHRAE levels have been a stumbling block for credit compliance, but with proper documentation supported by a clear narrative, this challenge can be overcome. There is an option to not include those fixtures in the LPD calculations and light trespass requirement, but you must demonstrate that these fixtures are full cutoff. To document the credit, make the case that the legally mandated fixtures are beyond the control of the project. Demonstrate that the project has met the requirements with rest of the lighting. Provide a detailed photometric plan, the municipal regulations, and a narrative describing how the project has achieved all requirements of the credit except where the municipal regulations overrule it.

Construction Documents

Expand All

  • Confirm all the lighting fixtures are listed on the lighting plan. This ensures that the correct components are purchased and installed to maintain the credit requirements.


  • The designer reviews the final bid documents and budget estimates to confirm that the fixtures have not been substituted for by another type, and that interior lighting controls and window shades are not omitted. 


  • If your team undertakes a value engineering process, make sure the full cutoff fixtures are not eliminated from the list or replaced by incandescent or high-powered halogen fixtures. These changes are often overlooked and may cost the project this credit.


  • If the project is going for multi-party contractor bid, make sure the bid’s package reflects the fixture specifications and performance. Otherwise the contractor may replace the specification with a similar lower-cost fixture that doesn’t have the same wattage or a cover for cutoff.


  • Full-cutoff luminaires should not cost more than conventional fixtures, but other common strategies for meeting this credit may add costs. These include controls, timers, sensors, and  low-power lights like LEDs. Ensure that these features are not eliminated during value-engineering.       

Construction

Expand All

  • The designer should review shop drawings and visit the site for installation inspection. This ensures that the fixtures have a cut-off for uplighting, the ballasts are as specified, and the controls are all included.


  • The commissioning agent carries out the functional testing for all control sequences and timers if installed for lighting design.

Operations & Maintenance

Expand All

  • Timer controls and automatic switches should be commissioned and inspected for performance periodically throughout their life to ensure they continue to serve the intent of the credit requirements.


  • The facility manager should be involved in the decision of whether to select light timers or automated blinds to comply with interior lighting requirements. Both solutions offer opportunities and challenges during building use, depending on how the building is used and occupied.


  • Long-life, low-power lamps like fluorescents and LEDs will help keep costs low for operations and maintenance.

  • USGBC

    Excerpted from LEED 2009 for New Construction and Major Renovations

    SS Credit 8: Light pollution reduction

    1 Point

    Intent

    To minimize light trespass from the building and site, reduce sky-glow to increase night sky access, improve nighttime visibility through glare reduction and reduce development impact from lighting on nocturnal environments.

    Requirements

    Project teams must comply with one of the two options for interior lighting AND the requirement for exterior lighting.

    For interior lighting

    Option 1

    Reduce the input power (by automatic device) of all nonemergency interior luminaires with a direct line of sight to any openings in the envelope (translucent or transparent) by at least 50% between 11 p.m. and 5 a.m. After-hours override may be provided by a manual or occupant-sensing device provided the override lasts no more than 30 minutes.

    OR

    Option 2

    All openings in the envelope (translucent or transparent) with a direct line of sight to any nonemergency luminaires must have shieldingShielding is a nontechnical term that describes devices or techniques that are used as part of a luminaire or lamp to limit glare, light trespass, or sky glow. (controlled/closed by automatic device for a resultant transmittance of less than 10% between 11 p.m. and 5 a.m.).

    For exterior lighting

    Light areas only as required for safety and comfort. Exterior lighting power densities shall not exceed those specified in ANSI/ASHRAE/IESNA Standard 90.1-2007 with Addenda i for the documented lighting zone. Justification shall be provided for the selected lighting zone. Lighting controls for all exterior lighting shall comply with section 9.4.1.3 of ANSI/ASHRAE/IESNA Standard 90.1- 2007, without amendments1.

    Classify the project under 1 of the following zones, as defined in IESNA RP-33, and follow all the requirements for that zone:

    LZ1: Dark (developed areas within national parks, state parks, forest land and rural areas)

    Design exterior lighting so that all site and building-mounted luminaires produce a maximum initial illuminance value no greater than 0.01 horizontal and vertical footcandlesVertical footcandles occur on a vertical surface. They can be added together arithmetically when more than 1 source provides light to the same surface. (0.1 horizontal and vertical luxMeasurement of lumens per square meter.) at the LEED project boundary and beyond. Document that 0% of the total initial designed fixture lumens (sum total of all fixtures on site) are emitted at an angle of 90 degrees or higher from nadir (straight down).

    LZ2: Low (primarily residential zones, neighborhood business districts, light industrial areas with limited nighttime use and residential mixed-use areas)

    Design exterior lighting so that all site and building-mounted luminaires produce a maximum initial illuminance value no greater than 0.10 horizontal and vertical footcandles (1.0 horizontal and vertical lux) at the LEED project boundary and no greater than 0.01 horizontal footcandlesHorizontal footcandles occur on a horizontal surface. They can be added together arithmetically when more than 1 source provides light to the same surface. (0.1 horizontal lux) 10 feet (3 meters) beyond the LEED project boundary. Document that no more than 2% of the total initial designed fixture lumens (sum total of all fixtures on site) are emitted at an angle of 90 degrees or higher from nadir (straight down).

    LZ3: Medium (all other areas not included in LZ1, LZ2 or LZ4, such as commercial/ industrial, and high-density residential)

    Design exterior lighting so that all site and building-mounted luminaires produce a maximum initial illuminance value no greater than 0.20 horizontal and vertical footcandles (2.0 horizontal and vertical lux) at the LEED project boundary and no greater than 0.01 horizontal footcandles (0.1 horizontal lux) 15 feet (4.5 meters) beyond the site. Document that no more than 5% of the total initial designed fixture lumens (sum total of all fixtures on site) are emitted at an angle of 90 degrees or higher from nadir (straight down).

    LZ4: High2 (high-activity commercial districts in major metropolitan areas)

    Design exterior lighting so that all site and building-mounted luminaires produce a maximum initial illuminance value no greater than 0.60 horizontal and vertical footcandles (6.5 horizontal and vertical lux) at the LEED project boundary and no greater than 0.01 horizontal footcandles (0.1 horizontal lux) 15 feet (4.5 meters) beyond the site. Document that no more than 10% of the total initial designed fixture lumens (sum total of all fixtures on site) are emitted at an angle of 90 degrees or higher from nadir (straight down).

    LZ2, LZ3 and LZ4 - For LEED project boundaries that abut public rights-of-way, light trespass requirements may be met relative to the curb line instead of the LEED project boundary.

    For all zones

    Illuminance generated from a single luminaire placed at the intersection of a private vehicular driveway and public roadway accessing the site is allowed to use the centerline of the public roadway as the LEED project boundary for a length of 2 times the driveway width centered at the centerline of the driveway.

    1The requirement to use ASHRAE Addenda is unique to this credit and does not obligate Project teams to use ASHRAE approved addenda for other credits.
    2 To be LZ4, the area must be so designated by an organizations with local jurisdiction, such as the local zoning authority.

    Credit substitution available

    You may use the LEED v4 version of this credit on v2009 projects. For more information check out this article.

    Potential Technologies & Strategies

    Adopt site lighting criteria to maintain safe light levels while avoiding off-site lighting and night sky pollution. Minimize site lighting where possible, and use computer software to model the site lighting. Technologies to reduce light pollution include full cutoff luminaires, low-reflectance surfaces and low-angle spotlights.

Organizations

Illuminating Engineering Society of North America

This organization provides general exterior lighting design guidance.


International Dark-Sky Association IDA

Links to manufacturers with IDA-approved fixtures, information sheets and practical guides, and resources for learning.


Lighting Research Center

This website is associated with the Lighting Research Center at Rensselaer Polytechnic.

Software Tools

SUPERLITE 2.0 ( Lawrence Berkeley National Laboratory)

SUPERLITE 2.0 is a lighting analysis program designed to accurately predict interior illuminance in complex building spaces due to daylight and electric lighting systems.


Litescape 3.0 (Standard Performance Evalutation Corporation)

Lighting simulation software.


Visual 3D

For someone who does not design lighting as their primary service, this free lighting calculation software can be downloaded here.

Other

Elights (Dark-Sky Lighting Products)

Elights sells full cut-off light fixtures.

Technical Guides

Lighting Power Density

A comprehensive source for understanding the lighting models underlying the commercial lighting power limits developed in ASHRAE/IESNA 90.1-2004.


Outdoor Site-Lighting Performance: A Comprehensive and Quantitative Framework for Assessing Light Pollution

This paper describes a method of measuring and predicting glow, glare and trespass in outdoor lighting.


Lighting for Exterior Environments

This publication from the Illuminating Engineering Society defines urban lighting zones according to population density.

Exterior Lighting Power Density

All Options

Perform calculations to demonstrate credit-compliance with exterior lighting power density requirements.

Compliant Light Fixtures

Refer to manufacturer cut sheets for the angle of light spilling above horizontal, the candela graph for maximum candela notation, and watts.

Intersection of Driveway and Roadway

This graphic illustrates SSc8's particular rule for how the site boundary relative to illuminance can expand when a driveway meets a public roadway.

Luminaire Schedule

The schedule lists all the exterior fixtures that will be accounted for in the the lighting power density calculations required for this credit.

Exterior Lighting Layout

Provide documentation like this example to showcase the exterior lighting layout plan. You'll refer to this plan in providing fixture and photometric analysis.

Annotated Photometric Plans

This set of annoatated photometric plans was created by Bill Swanson, P.E. for LEEDuser as a teaching tool for SSc8 documentation issues. They are not intended as examples of actual documentation, though a lot can be learned from them. These documents include a detailed plan showing a compliant site with light levels in the site and as required around the boundary, with advice and useful tips. The fixture comparison document is a means to better understand and compare the spill light from different light fixtures and placements. Think of the purple line as the edge of a cutout with a pin thru the paper where the pole is.  Move the cutout over the site when locating poles, if the cutout overlaps the line beyond the property line then that fixture cannot be located and aimed as placed. The driveway entrance example shows the impact of fixture placement around driveway entrances, and the special allowance for the site boundary around those entrances.

LEED Online Forms: NC-2009 SS

The following links take you to the public, informational versions of the dynamic LEED Online forms for each NC-2009 SS credit. You'll need to fill out the live versions of these forms on LEED Online for each credit you hope to earn.

Version 4 forms: (newest)

Version 3 forms:

These links are posted by LEEDuser with USGBC's permission. USGBC has certain usage restrictions on these forms; for more information, visit LEED Online and click "Sample Forms Download."

Design Submittal

PencilDocumentation for this credit can be part of a Design Phase submittal.

488 Comments

0
0
Lawrence Lile Chief Engineer Lile Engineering LLC
Apr 14 2014
LEEDuser Member
824 Thumbs Up

LZ1 vs LZ2 vs LZ3

We are working on a maintenance facility for a landfill (Don't worry - there is a big compost and container recycling operation there too!) They will be operating and maintaining garbage trucks. Normally I'd want to say this is LZ3 (commercial/industrial). However the landfill is located in the middle of a 600 acre site in a rural area. This makes me lean toward LZ1, the most restrictive category for site lighting.

How would you expect a LEED reviewer to call this one?

1
1
0
Bill Swanson PE, LEED AP, Integrated Architecture Apr 15 2014 LEEDuser Expert 13735 Thumbs Up

I've long complained that the lighting zone definitions are vague. That you are debating between LZ1 and LZ3 is sad. Things should not be this confusing. I don't know how a LEED reviewer would call this. Most of the time they seem to defer to the submitter's opinion but they have been known to disagree.

If there is a single building I would lean toward LZ1. If there is a complex of several buildings with activity outside most of the night I would lean towards LZ3 just around the buildings and then at some distance draw a line and say everything past this line is LZ1. Very arbitrary. If you can split the difference try submitting at LZ2.

Post a Reply
0
0
Anne Harney Senior Associate Ayers Saint Gross Architects + Planners
Mar 11 2014
LEEDuser Member
200 Thumbs Up

BUG Rating for Full-Cutoff Compliance

An exception is noted in the above requirements "If locally mandated lighting is higher than ASHRAE, you can still get the credit if you use full cutoffA full cutoff luminaire has zero candela intensity at an angle of 90 degrees above the vertical axis (nadir or straight down) and at all angles greater than 90 degrees from straight down. Additionally, the candela per 1,000 lamp lumens does not numerically exceed 100 (10%) at an angle of 80 degrees above nadir. This applies to all lateral angles around the luminaire. fixtures and make your case well". How does a fixture's BUG Rating compare to ASHRAE 90.1-2007 requirements for the project zone per IESNA RP-33.

1
6
0
Bill Swanson PE, LEED AP, Integrated Architecture Mar 11 2014 LEEDuser Expert 13735 Thumbs Up

Your wording is a little confusing. Are you trying to quote from the Checklist tab under Design Development?

What are you trying to do for your project?

BUG rating has nothing to do with this version of the credit. You may use the v4 credit language if you want to use the BUG rating.

2
6
0
Anne Harney Senior Associate, Ayers Saint Gross Architects + Planners Mar 11 2014 LEEDuser Member 200 Thumbs Up

Currently, our State Law prohibits the use of State funds to install or replace a permanent outdoor luminaire for lighting on the grounds of any State building or facility, unless, for a luminaire with an output of more than 1,800 lumens, the luminaire is a restricted uplight luminaire (allows no direct light emission above a horizontal plane through the luminaire’s lowest light-emitting part).

We have a bill being considered in current legislative session that introduces a BUG rating option as opposed to the full cutoffA full cutoff luminaire has zero candela intensity at an angle of 90 degrees above the vertical axis (nadir or straight down) and at all angles greater than 90 degrees from straight down. Additionally, the candela per 1,000 lamp lumens does not numerically exceed 100 (10%) at an angle of 80 degrees above nadir. This applies to all lateral angles around the luminaire. fixture requirement, mandated for state funded projects replacing more than 25% of existing fixtures.

Our project is a public University with a LEED Gold Certification goal. Our LEED site boundary includes existing site lighting which will need to be replaced, as well as a new proposed site lighting plan. LEEDv2009 NC dictates site lighting selection is a full-cutoff fixture. But it may be best for the University to select a fixture that meets the BUG requirements. I see BUG is an option in v4. Is that in lieu of the calculation method?

3
6
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Mar 12 2014 Guest 1241 Thumbs Up

Anne,

Can you tell me what State you are in? I'm very interested in state level light pollution control legislation.

Per USGBC, the v4 version of the credit can be used now on LEED-2009 projects. The v4 version allows you to use the BUG method to meet the Uplight limits and/or to meet the Trespass limits. Read the credit language carefully, the requirements are pretty clear.

I do not believe that LEED-2009 NC SS8 "dictates site lighting selection is a full-cutoff fixture". It just limits the amount of light above horizontal and the amount of light at the boundary. Where do you see that requirement?

4
6
0
Bill Swanson PE, LEED AP, Integrated Architecture Mar 12 2014 LEEDuser Expert 13735 Thumbs Up

State law trumps LEED. If you comply with the current law it sounds like your uplight won't be an issue. Will your project be done by the time the proposed bill becomes an enforced law?

As Glenn mentioned there is nothing in v2009 that requires full-cutoff fixtures. But the total site limit for uplight is very low.

5
6
0
Anne Harney Senior Associate, Ayers Saint Gross Architects + Planners Mar 12 2014 LEEDuser Member 200 Thumbs Up

Maryland State Law 14-412

6
6
0
Bill Swanson PE, LEED AP, Integrated Architecture Mar 17 2014 LEEDuser Expert 13735 Thumbs Up

Weird, there are two laws with the same identification.

Post a Reply
0
0
Saud Abdul Rasheed LEED Engineer Al Yamama Company
Mar 03 2014
LEEDuser Member
69 Thumbs Up

Exterior Lighitng: Facade Lighting

Hello All,
My question may be simple but still I want to be clear about it. When we are calculating the exterior lighting, in LEED Reference Guide as well as ASHRAE 90.1 2007 we have the units either as "watts per linear foot/metet" or "watts per square feet/square meter"?. For example in the latest addendum of the ligthing credit in SS it says for LZ2 the LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. for Facade lighting is 0.1W/ft2 or 2.5W/linear meter. How can I calculate these do I need all the Facade area for both calculations? and how I can convert from linear meters to square meters or vice verse?

1
4
0
Gustavo De las Heras Izquierdo Arch. Eng. LEED AP BD+C, Revitaliza Consultores Mar 03 2014 Guest 30 Thumbs Up

In my opinion:
-Area: you have to measure the facade area in the elevation drawing.
-Linear: you have to measure the length of the facade (floor plan)

2
4
0
Saud Abdul Rasheed LEED Engineer, Al Yamama Company Mar 03 2014 LEEDuser Member 69 Thumbs Up

Thanks Gustavo.

- Do I measure all the facade area and then distribute lighting in the area so that total Watts per meter square does not exceed the total LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. limit for the whole area?

- For linear calculation I am not sure how to do it. If i only measure the length I will still be having width of the facade so depending on this I may be installing lights on the length from two sides of the width or even three lines of lighting along the length of facade depending on the width.

3
4
0
S S Mar 03 2014 Guest 40 Thumbs Up

The above said opinion is correct. Further no need to convert from linear meters to square meters or vice verse.If the light fittings are located to illuminate the whole façades, then you need to calculate watts per square meters method otherwise you can go with watts per linear meters method.

4
4
0
Saud Abdul Rasheed LEED Engineer, Al Yamama Company Mar 04 2014 LEEDuser Member 69 Thumbs Up

Thank you!

Post a Reply
0
0
James Weingarten Electrical Designer MEP Associates
Feb 27 2014
Guest
113 Thumbs Up

Interior Shut off vs Safety

In version 2009, I have to shutoff or reduce interior lighting. The interior space is a chiller plant where lighting shutoff or reduction would create a safety risk. Ashrae allows me to "exempt" these areas from automatic shutoff controls. Does LEED as well? Or would I be required to provide shades on windows between 11 and 5?

1
1
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Feb 27 2014 Guest 1241 Thumbs Up

James,
I don't think they'd allow that exemption, but remember that you are allowed "after hours override".

Are you aware that there are no interior lighting requirements in the v4 version of this credit and that you can now use the LEED v4 version of this credit on LEED-2009 projects.
http://www.usgbc.org/node/2600382?return=/credits/new-construction/v4/su...
http://www.usgbc.org/articles/use-v4-credits-your-v2009-project?utm_sour...

If you can meet the 2009 requirements you'll very likely meet the v4 requirements. In general the credit is less complicated and easier to use.

Post a Reply
0
0
Donald Green Project Manager Sustainable Design Consulting, LLC
Feb 26 2014
LEEDuser Member
332 Thumbs Up

Event Center

Is there any exception to a project that would only be used 12 times a year (1 time per month) past the 11pm time line for interior lighting levels? The project would otherwise meet the requirements for the 50% cut off the other 353 days of the year. The project would be in LZ4 and surrounded by other like uses that typically would be closed at that hour anyways.

1
3
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Feb 26 2014 Guest 1241 Thumbs Up

Donald,
There are no interior lighting requirements in the v4 version of this credit.
You can now use the LEED v4 version of this credit on LEED-2009 projects.
http://www.usgbc.org/node/2600382?return=/credits/new-construction/v4/su...
http://www.usgbc.org/articles/use-v4-credits-your-v2009-project?utm_sour...

If you can meet the 2009 requirements you'll likely meet the v4 requirements. In general the credit is less complicated and easier to use.

You should also be careful about claiming LZ4. Unless you are in Times Square NYC or Las Vegas Strip or something like it, you may be questioned by the reviewer.

2
3
0
Donald Green Project Manager, Sustainable Design Consulting, LLC Feb 27 2014 LEEDuser Member 332 Thumbs Up

Thanks for the information, I guess downtown Richmond, VA isn't quite NYC... so I guess we will look into LZ3.

Thank you,

3
3
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 27 2014 LEEDuser Expert 13735 Thumbs Up

On a different credit I was told once by a reviewer that a board room that was occupied once a month was considered "regularly occupied" and therefore must comply with the credit requirements. Assume all rooms must comply with this credit. Rarely used doesn't seem to be a justification they accept.

Post a Reply
0
0
Jens Apel
Feb 11 2014
LEEDuser Member
702 Thumbs Up

Hotel guest rooms = dwelling units

I understand that residential units are exempt from interior lighting requirements. Does this include hotel guest rooms as well?

1
2
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 11 2014 LEEDuser Expert 13735 Thumbs Up

Per Omar Katanani on Feb 26 2013

I got a very clear answer from the USGBC:

"The residential exemption cannot be applied to hotel rooms."

2
2
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Feb 11 2014 Guest 1241 Thumbs Up

Jens,

There are no interior lighting requirements in the v4 version of this credit.

You can now use the LEED v4 version of this credit on LEED-2009 projects.
http://www.usgbc.org/node/2600382?return=/credits/new-construction/v4/su...

http://www.usgbc.org/articles/use-v4-credits-your-v2009-project?utm_sour...

Post a Reply
0
0
ÅF Lighting ÅF Infrastructure
Feb 11 2014
LEEDuser Member
2 Thumbs Up

ULR compliance and indirect light

We are developing a principal design for an industrial building within zone LZ2 or 3, depending on where it is located in the world. I wonder wether it will be accepted to have lighting pointing towards the ground or some other bright surface and utilising the indirect light for facade lighting.
In a way the question concerns how they look at light fixtures and where they "end" so to say.

I know this could be seen as a way of sidestepping the intention of the credit. But I dare to suggest it because:
1. Being a professional lighting designer I know how to make the light go where I want it.
2. LEED's inflexible regulations that only look at fixture lumens above horizontal.

1
3
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 11 2014 LEEDuser Expert 13735 Thumbs Up

Your approach does seem to side step the intent of the credit. Following the intent of the credit is just as important as following the technical details of complying with the credit.

Like I've told others before, you can try to submit but don't expect the credit in your point totals.

I'd be curious as to how reflective is the surface you intend to bounce the light off of. If it is shiny metal or mirror I'd say no way. If it is white paint I'd me more likely to agree with you. Also I'd make sure to clearly note that this surface is separate from the light fixture, even supplied by a different manufacturer.

2
3
0
ÅF Lighting ÅF Infrastructure Feb 11 2014 LEEDuser Member 2 Thumbs Up

Thank's that was a quick reply. It did raise some new questions though.
If the intent of the credit is as important as the technical detail. Could a case be made if we were able to show that our facade lighting only produced 2-5% uplight, regardless of aiming.
It would follow the intent but be a completely different principle of measuring uplight.

3
3
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 17 2014 LEEDuser Expert 13735 Thumbs Up

Yes, you can shine the façade light up if the total uplight for the site is below the limit for your lighting zone.

Post a Reply
0
0
Sahar Abi-Ziki
Feb 06 2014
Guest
40 Thumbs Up

Questions

We are trying to achieve this credit, I have 2 questions;
- The municipality has few lighting off our site limit but very close to our LEED boundary. Should we include them in the calculation even if we do not have control of it and it is off our site? I guess the intention of this credit is to study how our lighting density affects surrounding sites and not the opposite.
- Should we include in calculations of exterior power density any occasional exterior lighting? We have exterior plugs and occasionally to increase lighting for special outside events extra lights might be added. I cannot include it in the calculations since I don’t know what type they will be using.
Thank you !

1
1
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 06 2014 LEEDuser Expert 13735 Thumbs Up

1) The municipal lights are not included in the calculations.

2) Per ASHRAE 90.1-2007, 9.4.5 has exception f. that says temporary lighting with an independent control device is exempt from the exterior power allowance.

Post a Reply
0
0
Jens Apel
Feb 04 2014
LEEDuser Member
702 Thumbs Up

Historical building, facade lighting, light trespass

We work on a major renovation of a historical building with zero plot line in an LZ3 commercial centre. The facades will be lighted. I understand that the facade lighting is not exempt from the maximum 5% lumens going up. It is exempt from the exterior lighting power allowance.
Can we claim an exemption of the facade lighting only with regard to the light trespass calculation? Even when taking the curb line instead of plot line this may be difficult.
Thanks, Jens

1
4
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 04 2014 LEEDuser Expert 13735 Thumbs Up

Façade lighting is not exempt from the exterior lighting power allowance. It is in a different category called non-tradable surfaces.

The façade lighting needs to be included in the light trespass calculation.

If the curb is on a public street you may be able to extend the lighting boundary to the centerline of the street.

2
4
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Feb 04 2014 Guest 1241 Thumbs Up

Jens,

You can now use the LEED v4 version of this credit on LEED-2009 projects.
http://www.usgbc.org/node/2600382?return=/credits/new-construction/v4/su...
This will allow you to exempt the facade lighting in LZ3 from the uplight and trespass limits as long as it is shut off 0:00-06:00.
All exterior lighting, including facade lighting, is still required to comply with the 90.1 LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. limits per EApr2
This version of the credit uses the new Lighting Boundary, which allows you to move the trespass calculation line out to the center of the public street or 5ft. into other public property - maybe that will help.

3
4
0
Jens Apel Feb 10 2014 LEEDuser Member 702 Thumbs Up

Bill,
thanks for your reply. Just to make sure I got it right: The project is a registered historic building. According to ASHRAE 90.1 section 9.4.5 I understand facade ligting is excempt from LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. allowance. Is this correct?
BUT we need to comply with LEED requirements of light-trespass and max 5% uplight.

4
4
0
Bill Swanson PE, LEED AP, Integrated Architecture Feb 10 2014 LEEDuser Expert 13735 Thumbs Up

Sorry I misunderstood you. I was thinking of façade lighting as something different. Lighting used to highlight features of a historic building is exempt from ASHRAE 90.1 light power density limits as you've noted.

And then you need to comply with LEED requirements for light trespass and uplight limits. This is a problem for most projects that use these exemptions. A high school with a sports field lighting is almost impossible.

Post a Reply
0
0
S S
Jan 20 2014
Guest
40 Thumbs Up

ULR (Upward Light Ratio) Difference

We are doing external lighting simulation for factory building. We are using 250W street light fitting (10nos) and there is no other type of lights. Our strategy is to provide optimum luxMeasurement of lumens per square meter. level & uniformity on road surface. So that we have given the tilt angle of 20deg for all light fittings. Because of this angle, the total upward ratio is exceeding more 5% (which has calculated by lighting software). But as per the photometric property, ULR is 2.5% without considering the tilt angle. Our doubt is which one has to be considered for LEED Submission whether ULR considering tilt angle or ULR without considering tilt angle. Please reply...
Is there any strategies to reduce ULR to below 5% without changing the light fittings & tilt angle.

1
1
0
Bill Swanson PE, LEED AP, Integrated Architecture Jan 20 2014 LEEDuser Expert 13735 Thumbs Up

The uplight has to be calculated based on how the fixture is installed. If you are tilting the fixture at 20° then this must be considered in your uplight calculation.

Either the housing or the tilt angle will need to be changed to get the uplight below 5%.

Can you space the fixtures closer together so you don't need to tilt them? Have you looked at some good quality LED fixtures that can control light output better than an HID fixture?

Post a Reply
0
0
Deborah Zimmerman Michaud Cooley Erickson
Jan 07 2014
Guest
8 Thumbs Up

Relocated "globe" fixtures on campus

We have a new construction project on an existing campus setting. To make room for the new building, an existing sidewalk has been relocated along with the existing light standards. The existing fixtures are a "globe" style fixture (i.e.: light emitted at 360 degrees). There are only a few of these fixtures, but I'm not sure that we can track down the photometric information for them. I assume that we will need to include these in our calculations.... or tweak the project boundary. Thoughts?

1
2
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Jan 08 2014 Guest 1241 Thumbs Up

Yes, all fixtures within the LEED Project Boundary have to be included in the calculations. On a recent project with existing fixtures where no photometrics were available, we used an educated estimate and explained in the narrative how we made that estimate . We'll see what the GBCI reviewer says.

2
2
0
Bill Swanson PE, LEED AP, Integrated Architecture Jan 08 2014 LEEDuser Expert 13735 Thumbs Up

The uplight limit is fairly small. Even a couple flag lights will often use it up. Without knowing how large your lighting boundary is or how many other full cutoffA full cutoff luminaire has zero candela intensity at an angle of 90 degrees above the vertical axis (nadir or straight down) and at all angles greater than 90 degrees from straight down. Additionally, the candela per 1,000 lamp lumens does not numerically exceed 100 (10%) at an angle of 80 degrees above nadir. This applies to all lateral angles around the luminaire. fixtures will be in the count I'd guess these globe lights will put you over the limit.

Look up the lamp information. Either packaging from the maintenance shelf or on a typical lamp manufacturer's website. You need the initial lamp lumen1. A lumen is a unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of 1 candle intensity. 2. A measurement of light output. value. Then, if the fixture is fluorescent or HID you need to know the ballast factor of the ballast. Multiply the ballast factor by the initial lamp lumens to get the total lamp lumens for the bare lamp. This is the total fixture lumen value you need to use when you don't have a photometric file or any other data about the fixture. Multiply by 50% to get the uplight value for a globe light.

Post a Reply
0
0
Lyle Axelarris Civil Engineer, LEED AP BD+C, O+M Design Alaska
Dec 20 2013
LEEDuser Member
333 Thumbs Up

Translucent "Daylighting" Panels - count as "shielded" openings?

We have insulated, translucent daylighting panels on the project, and I'm wondering if they will be considered "windows" for the interior lighting requirements of this credit. If Option 1 (power reduction) is not possible, can Option 2 (window shieldingShielding is a nontechnical term that describes devices or techniques that are used as part of a luminaire or lamp to limit glare, light trespass, or sky glow.) be applied here automatically? Option 2 allows for "automatic shades that have less than 10% transmittance" (Ref. Guide, p. 134), so will daylighting panels that have a VLT less than 10% automatically count as being "shaded"?
Thanks for your help.

1
2
0
Bill Swanson PE, LEED AP, Integrated Architecture Dec 23 2013 LEEDuser Expert 13735 Thumbs Up

The credit language does not say "windows" but "openings". If light can pass thru it then it is an opening.

It sounds reasonable. Submit a cutsheet of the panels that identifies the VLT. You may also want to clarify where in the building this is being used since I doubt every opening has this panel in it. And remember to show compliance for every other opening using either Option 1 or 2.

2
2
0
Lyle Axelarris Civil Engineer, LEED AP BD+C, O+M, Design Alaska Dec 26 2013 LEEDuser Member 333 Thumbs Up

Thanks, Bill.

Post a Reply
0
0
Alfred Servodidio Project Manager JMV Consulting Engineering
Dec 11 2013
LEEDuser Member
22 Thumbs Up

Historic building facade highlighting 24/7

Our project is an historic building in the flatiron district in NYC. The building is being designed with facade uplights around each floor of the entire building.
It is being discussed to have the lights illuminated 24/7.
Will this automatically prvent us from achieving this credit?

1
1
0
Bill Swanson PE, LEED AP, Integrated Architecture Dec 11 2013 LEEDuser Expert 13735 Thumbs Up

That depends. This being NYC I'm assuming you don't have a lot of parking lot lighting. The credit language is based on % of uplight for the whole site. If you don't have a lot of other lighting on the exterior then this will prevent you from achieving this credit.

Can you put LED lights at the top of the building and shine them down?

Post a Reply
0
0
Emmanuel Pauwels Owner Green Living Projects s.l.
Dec 02 2013
LEEDuser Member
1509 Thumbs Up

Landscape Allowance

We are working on a Project that will have exterior lighting in the landscape areaThe landscape area is the total site area less the building footprint, paved surfaces, water bodies, and patios..
We should include landscape lighting in the calculations?
Does Ashrae allow landscape lighting?

Our approach would be to calculate the exterior lighting power allowance with the tradable surfaces (walkways, parking..) in table 9.4.6 and consider it as the exterior lighting power allowance for all the project (tradable surfaces listed + landscape).
With this approach, do we comply with the Ashrae mandatory and the credit requirements for exterior lighting power allowance?

1
5
0
Bill Swanson PE, LEED AP, Integrated Architecture Dec 02 2013 LEEDuser Expert 13735 Thumbs Up

All exterior lighting that is not exempted in 9.4.5 must be included in the energy calculation. So landscape lighting must be included.

I'll assume your project was registered in the past couple of years. The updated table for this credit has a line item under Tradable Surfaces for Landscaping. Not much, about 0.05 W/sf. If you have any paths going thru the landscaped area I would also count it as a Walkway less than 10 feet wide.

Don't forget to use the new Base Site Allowance. This can be used for anything on the site. So, all of your Tradable Surfaces (which includes landscape lighting) must be less than your Base Site Allowance + Tradable Surfaces allowance.

2
5
0
Emmanuel Pauwels Owner, Green Living Projects s.l. Dec 03 2013 LEEDuser Member 1509 Thumbs Up

OK, thanks.
And what about the roof areaRoof area is the area of the uppermost surface of the building which covers enclosed Gross Floor Area, as measured when projected onto a flat, horizontal surface (i.e. as seen in Roof Plan view). ‘Roofs’, or portions of roofs, covering unenclosed areas (e.g. roofs over porches and open covered parking structures) are not included in the areas used to evaluate compliance with SSc7.2, though they may be applicable to SSc7.1. in case it has an area where people can sit. Do we include lighting on the roof area in the calculations?

3
5
0
Bill Swanson PE, LEED AP, Integrated Architecture Dec 03 2013 LEEDuser Expert 13735 Thumbs Up

Yes, the roof top lighting is exterior to the building and should be included.

4
5
0
Emmanuel Pauwels Owner, Green Living Projects s.l. Dec 03 2013 LEEDuser Member 1509 Thumbs Up

Thank you Bill.
If we have an entry door that is not lighted, can we count this allowance to determine the lighting budget?
We have also some walkways and canopies that are partially lighted. Can we count the allowance for all the surfaces of the walkways and canopies, even if there is a part that will not be lighted in the project?
Is the calculation of the LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. for SSc8 the same for the baseline model for EAp2?

5
5
0
Bill Swanson PE, LEED AP, Integrated Architecture Dec 03 2013 LEEDuser Expert 13735 Thumbs Up

As far as I know only façade lighting requires the surface to be illuminated before it can be counted in the allowance.

I count every door, canopy, or walkway in the exterior lighting allowance. Regardless if it is illuminated or not.

I'd be surprised if your entry door is not lighted. Any path of egress requires lighting on the outside. At least in the US. Unless your door is not a path of egress. Most are, but it is possible.

Post a Reply
0
0
Michael Johnson Architect Chenevert Architects
Nov 20 2013
LEEDuser Member
387 Thumbs Up

light trespass vs hardscape

project is along an arterial road with lots of city lights. i see the leed interpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. #10114 - which allows leed boundary to be extended outward to midline of street in this scenario.

my question is, does leed allow this boundary extension to apply only to its inherent issue with light pollution credit? or do we have to apply this leed boundary to everything?

If everything, it becomes a little bit ridiculous - because the "project hardscapeHardscape consists of the inanimate elements of the building landscaping. Examples include pavement, roadways, stone walls, concrete paths and sidewalks, and concrete, brick, and tile patios." begins to include the pavement of the major thruway.

1
7
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Nov 20 2013 Guest 1241 Thumbs Up

The LEED interpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. creates a new separate thing called the Lighting Boundary. The LEED Project Boundary still exists. For the purposes of SS8 the light trespass calculations are now made at The Lighting Boundary. But the fixtures that have to be included in the calculations for both the trespass and uplights limits are only those within the LEED Project Boundary. And, as usual, the LEED project Boundary must be the same across all Site credits that use it

2
7
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Nov 20 2013 Guest 1241 Thumbs Up

FYI The interpretation you should be looking at is 10236 I believe

3
7
0
Deborah Zimmerman Michaud Cooley Erickson Jan 30 2014 Guest 8 Thumbs Up

I had the same question that Michael had and understood the Interpretation 10114 to be the way that Glenn has explained. So, another question...
The Interpretation states that "When the property line is adjacent to a public street, alley or transit corridor, the lighting boundary may be moved to the center line of that street..." What exactly constitures the term "adjacent to"? Is it 1'? 5? 20? We have a situation where the property line is about 5' from a right-of-way to a public street. The right-of-way is about 15' wide. So, our property line is about 20' from the road. Are we able to then move our lighting boundary to the center line of the street?

4
7
0
Bill Swanson PE, LEED AP, Integrated Architecture Jan 30 2014 LEEDuser Expert 13735 Thumbs Up

I see "adjacent" to mean, is there anything else between the public way and the property line. Meaning, is there a separate property title or ownership? Sidewalk is still part of the public way, so is the grass on the parkway. I am working on a project right now that is next to an on ramp for the expressway. The centerline is a long way from the property line but that's what I'm using on that side.

The project boundary for other credits remains the same. But the lighting boundary for this credit can be moved to the centerline of the street.

5
7
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Jan 30 2014 Guest 1241 Thumbs Up

I believe that Bill's explanation is correct.
"Adjacent to" means coincident or abutting. BUT the terms "public street, alley or transit corridor" should not be taken too literally - that is to say, your property line does not have to be right at the curb. Perhaps a rewrite of this definition for clarity could go into an addendum someday.

6
7
0
Deborah Zimmerman Michaud Cooley Erickson Jan 31 2014 Guest 8 Thumbs Up

If our property line abutts a public right of way which then abutts a public sidewalk and street, then in this case we can extend our lighting boundary to the center of the street, correct?

7
7
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Feb 03 2014 Guest 1241 Thumbs Up

I think the answer is "yes", assuming that the distance from the property line to the street is not too great. How far is it from the property line to the curb? If the "right of way" area is just a band along the street, then I think it should be interpreted that you are "adjacent to a public street". But I suppose that if you are a long way away from the street, it might be interpreted that you are adjacent to a public walkway or plaza.

Post a Reply
0
0
Serena Penasa Engineer LEED AP BD+C
Nov 11 2013
Guest
18 Thumbs Up

Site lumen calculation_Historical building

Good morning,
I have a project in area LZ3 which is a listed historic building. The designer wants to insert uplights for exteriors lighting of facades. For ASHRAE 90.1 p. 60 paragraph 9.4.5, I can exclude Lighting used to highlight features of Public monuments and registered historic landmark structures or building for LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. calculation. Can I exclude it also for Site Lumen1. A lumen is a unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of 1 candle intensity. 2. A measurement of light output. Calculation (Table SSc8-3)?

thanks, best regards
Serena

1
5
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Nov 12 2013 Guest 1241 Thumbs Up

No, you cannot.

You might want to look at pursuing Pilot Credit #7 which exempts facade lighting from the uplight limits as long as you are in LZ3 or 4 and you shut it off at midnight

2
5
0
Serena Penasa Engineer LEED AP BD+C Nov 13 2013 Guest 18 Thumbs Up

Thanks for your reply.
According to you, can I compile the form SS 8 and then load calculation performed according to the Pilot 7 in the special circumstances in the bottom of the form?

Thanks, best regards
Serena

3
5
0
Bill Swanson PE, LEED AP, Integrated Architecture Nov 13 2013 LEEDuser Expert 13735 Thumbs Up

It does not sound like you can earn SSc8 since the uplight is not excluded. You can always try but don't get your hopes up.

As an alternative you can use an ID credit to go after Pilot Credit 7.

4
5
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Nov 13 2013 Guest 1241 Thumbs Up

Serena,

Pilot credit 7 is a completely separate version of the light pollution credit. It is the version of the credit that will be in LEED v4. Pilot credits count as one of your 5 possible Innovation and Design credits.

http://www.usgbc.org/node/2606845?return=/pilotcredits

There are no submittal forms yet for Pilot 7, so you have to put together your own submittal materials based on the credit requirements. Pilot 7 has two optional paths for the trespass and uplight control, and one path is basically the same as in LEED-2009. So since you are pursuing that path already you could probably use some of the LEED-2009 documentation format. Pilot 7 also has no interior lighting requirements, so you don't have to hassle with that.

5
5
0
Serena Penasa Engineer LEED AP BD+C Nov 26 2013 Guest 18 Thumbs Up

Thanks for your reply.
But if any permanent solid surface that blocks up light can be considered a shiled. How can I calculating what % of light is not blocked by the various surfaces?
For exmple a uplight under a balcony, or a unplight near a wall?
Thanks.
Best regards,
Serena

Post a Reply
0
0
S S
Oct 28 2013
Guest
40 Thumbs Up

Wattage Difference

We have received IES file for one of our lighting simulation project.
Here, the wattage of light fitting is 25W (As per brochure) but when we importing IES file to simulation software, the wattage is 28W. Why this discrepancy? Which one has to be considered? Whether that 28W is based on ballast losses?.. Pl help me..This type of confusion is raising in almost all the projects.

1
1
0
Bill Swanson PE, LEED AP, Integrated Architecture Oct 30 2013 LEEDuser Expert 13735 Thumbs Up

The wattage should be based on the combination of lamp and ballast. It sounds like you have a 25w lamp that uses 28w while running. Manufactuters will often put a running wattage in the ies file. The difference is commonly called ballast loss.

The 90.1 handbook has some default values to use for different lamp ballast combinations if you can't get a value from the manufacturer.

Post a Reply
0
0
S S
Oct 28 2013
Guest
40 Thumbs Up

Method of Calculating Exterior Lighting Power Density

Could any one tell me, the method of LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. Calc for exterior areas. How can i take exterior area correctly and without getting review comment.. Pl advise

1
1
0
Bill Swanson PE, LEED AP, Integrated Architecture Oct 30 2013 LEEDuser Expert 13735 Thumbs Up

No one can promise you won't get a review comment. I've explained the LPDLighting power density (LPD) is the amount of electric lighting, usually measured in watts per square foot, being used to illuminate a given space. calc a couple of times and provided example. Scroll thru previous comments. Measuring the area of pavement is the hardest part. You'll need to do this in CAD to get a quick and accurate number.

Post a Reply
0
0
Anya Fiechtl LEED AP BD+C, AIT CTA
Oct 11 2013
LEEDuser Member
539 Thumbs Up

"Lighting Boundary" definition and use

LEED interpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. 10236 (http://www.usgbc.org/leed-interpretations?keys=10236&=Search#) seems to indicate that the lighting boundary is a modification of the project boundary (e.g. 5' at parking lots or to centerline along public streets). It also says, "All instances in the credit language of "LEED project boundary" or "site boundary" shall be considered to refer to the "lighting boundary", for the purposes of this credit only."

So, when the LEED credit says, for LZ3... "produce a maximum initial illuminance value no greater than 0.20 horizontal and vertical footcandlesVertical footcandles occur on a vertical surface. They can be added together arithmetically when more than 1 source provides light to the same surface. at the LEED project boundary (aka "Lighting boundary") and no greater than 0.01 horizontal footcandlesHorizontal footcandles occur on a horizontal surface. They can be added together arithmetically when more than 1 source provides light to the same surface. 15 feet beyond the site (aka "Lighting boundary")."

... Am I interpreting this correctly that we FIRST establish the lighting boundary with allowances noted in the interpretation, THEN demonstrate 0.2 horiz/vert fc1. A footcandle (fc) is a measure of light falling on a given surface. One footcandle is defined as the quantity of light falling on a 1-square-foot area from a 1 candela light source at a distance of 1 foot (which equals 1 lumen per square foot). Footcandles can be measured both horizontally and vertically by a footcandle meter or light meter. 2. The non-metric measurement of lumens per square foot, one footcandle is the amount of light that is received one foot from a light source called a candela, which is based on the light output of a standardized candle. A common range for interior lighting is 10 to 100 footcandles, while exterior daytime levels can range from 100 to over 10,000 footcandles. Footcandles decrease with distance from the light source. The metric equivalent of a foot candle is 10.76 lux, or lumens per square meter. @ the modified lighting boundary, and 0.01 horiz fc @15' beyond that lighting boundary?

Please advise. Thanks!

1
1
0
Glenn Heinmiller IALD, LC, LEED AP, Principal, Lam Partners Oct 11 2013 Guest 1241 Thumbs Up

YES, is the answer to your question (assuming I'm understanding it). To clarify, the Lighting Boundary is the PROPERTY LINE, MODIFIED as allowed. All calculations are made relative the the Lighting Boundary, not the LEED Project Boundary. The LEED Project Boundary is only relevant to this credit in that the exterior fixtures that have to be counted, are those within the LEED Project Boundary

Post a Reply

Start a new LEED comment thread

Apr 23 2014
Type the characters you see in this picture. (verify using audio)
Type the characters you see in the picture above; if you can't read them, submit the form and a new image will be generated. Not case sensitive.

Copyright 2014 – BuildingGreen, Inc.